This proposal is for a K23 Mentored Patient-Oriented Career Development Award focused on cognitive functioning in older adults with bipolar disorder. The candidate plans to become an independent investigator focusing on cognitive dysfunction as a target to enhance overall functional outcomes in late-life bipolar disorder treatment. The candidate is a geriatric psychiatrist and post-doctoral research fellow at the University of Pittsburgh who will obtain training in cognitive science, including neuroscience and neuroimaging, to assess cognitive functioning in late-life bipolar disorder. Additional training will include intervention research methodology to develop interventions based on the findings of the proposed research. The application proposes a cross-sectional study of 80 euthymic patients with bipolar disorder ages 50 years and older (40 patients ages 50 - 65 years and 40 patients 65 years and older) and 40 age- and education- equated control subjects (20 for each age group) comparing cognitive functioning between bipolar patients and controls and examining differences in functional abilities (ADLs, lADLs) mediated by cognitive disturbances. The candidate will examine the relationship between cognitive status and the following illness variables: age of illness onset, illness course, history of psychotic symptoms, substance use, physical co-morbidity, medication side effect, APOE allele type, structural brain imaging abnormalities, and lifetime exposure to lithium or valproate. The training and research will be conducted under the auspices of the Advanced Center for Intervention and Services Research for Late-Life Mood Disorders and the Bipolar Disorder Center for Pennsylvanians at the University of Pittsburgh. The candidate's primary hypotheses are (1) older subjects with bipolar disorder will have greater cognitive disturbances than age- and education- equated controls, most pronounced in information processing speed, and (2) cognitive performance will be negatively associated with earlier, more severe course of bipolar disorder and additional illness variables.